1. Field of the Invention
This invention relates generally to transfer cartridges for receiving and storing a pre-cut length of photosensitive material. More particularly, this invention pertains to a unique light seal for such cartridge, such light seal assuming the form of an opaque, flexible belt operatively associated with a pair of rollers.
2. Description of the Prior Art
Diverse light seals have been employed to keep light from penetrating the interior of transfer cartridges and exposing the photosensitive material received therein. Such light seals have relied upon mechanical light traps, light tight housings, and other known expedients.
One known light seal is disclosed in U.S. Pat. No. 3,743,200, granted July 3, 1973, to Michel Hommerin. This patent discloses a magazine for storing film sheets for use in X-ray film handling apparatus. The magazine includes a light-tight housing 1 and a slot 2 for introducing, or ejecting, the sheets F, and further includes a motor driven central storage roller 10. A plastic flexible band 7 is wound, respectively, around two cylindrical rollers 5, 6 which close off the slot. The film sheet F introduced into the slot is wound on the central roller and is stored between two faces of the band fed from the feed roller. For ejection the feed roller is driven in the opposite direction to unwind the band from the central roller and carry the sheet toward the slot. A first motor 11 and a belt 12 drive the central roller 10 in one direction, while a second motor 13 and a second belt 14 drive the roller 8, which carries the excess length of the band 7, in the opposite direction.
Whereas Hommerin may function satisfactorily under most operating conditions, certain deficiencies are noted For example, such magazine requires a light-tight housing, which entails increased costs in manufacturing same. Such magazine relies upon cylindrical rollers 4, 5 to seal the slot in a light-tight manner; the surface of roller 4 has a supple surface. However, while the nip defined between the rollers may be satisfactory for handling X-ray film, the- nip may well destroy, or at least mar, the emulsion, found on photosensitive film. Also, the positioning of guides 17 and the drive rollers 8, 9 within the housing reduces the capacity of photosensitive material that can be received, and stored, therein.
Another X-ray film cassette, or cartridge, that receives, or dispenses, sheets of X-ray film in a light-tight manner is shown in U.S. Pat. No. 3,715,087, granted Feb. 18, 1971, to Gunter Schmidt. Here again, a light tight housing 40 is utilized in connection with a slidable solenoid operated light shield 130 (FIG. 2) to prevent exposure of the X-ray film within removable storage module 18. The film is wound on an opaque web 84 that is wound about drum 60, as shown in FIG. 1.